Doubly charged Higgs bosons

132

193

We continue our investigation of gauge theories in which the Higgs boson arises as a pseudo-Nambu-Goldstone boson (pNGB) and top-partners arise as bound states of three hyperfermions. All models have additional pNGBs in their spectrum that should be accessible at LHC. We analyze the patterns of symmetry breaking and present all relevant couplings of the pNGBs with the gauge fields. We discuss how vacuum misalignment and a mass for the pNGBs is generated by a loop-induced potential. Finally, we paint a very broad, qualitative, picture of the kind of experimental signatures these models give rise to, setting the stage for further analysis.

Section: Two More Pngbs/alpsmentioning

confidence: 99%

Section: Jhep06(2016)107mentioning

confidence: 99%

Gauge theories of partial compositeness: scenarios for Run-II of the LHC

Ferretti

2016

132

193

“…The first model predicts the Drell-Yan production of doubly charged Higgs bosons [21,22], which then decay into lepton pairs. The decays can include flavour-violating terms that can lead to final states such as ± τ ± ∓ τ ∓ , where denotes an electron or muon, and the tau lepton is allowed to decay hadronically or leptonically.…”

Section: Jhep08(2015)138mentioning

confidence: 99%

“…Final states including three or more charged, prompt, and isolated leptons have received significant attention, both in measurements of Standard Model (SM) diboson [1][2][3] and Higgs boson production [4,5], and in searches for new phenomena. Anomalous production of multi-lepton final states arises in many beyond the Standard Model (BSM) scenarios, including excited-lepton models [6,7], the Zee-Babu neutrino mass model [8][9][10], supersymmetry [11][12][13][14][15][16][17][18][19], models with pair production of vector-like quarks [20], and models with doubly charged Higgs bosons [21,22] including Higgs triplet models [23,24]. An absence of significant deviations from SM predictions in previous measurements and dedicated searches motivates an inclusive search strategy, sensitive to a variety of production modes and kinematic features.…”

Section: Introductionmentioning

confidence: 99%

Search for new phenomena in events with three or more charged leptons in pp collisions at s = 8 $$ \sqrt{s}=8 $$ TeV with the ATLAS detector

Aad¹,

Abbott²,

Abdallah³

et al. 2015

A generic search for anomalous production of events with at least three charged leptons is presented. The data sample consists of pp collisions at √ s = 8 TeV collected in 2012 by the ATLAS experiment at the CERN Large Hadron Collider, and corresponds to an integrated luminosity of 20.3 fb −1 . Events are required to have at least three selected lepton candidates, at least two of which must be electrons or muons, while the third may be a hadronically decaying tau. Selected events are categorized based on their lepton flavour content and signal regions are constructed using several kinematic variables of interest. No significant deviations from Standard Model predictions are observed. Model-independent upper limits on contributions from beyond the Standard Model phenomena are provided for each signal region, along with prescription to re-interpret the limits for any model. Constraints are also placed on models predicting doubly charged Higgs bosons and excited leptons. For doubly charged Higgs bosons decaying to eτ or µτ , lower limits on the mass are set at 400 GeV at 95% confidence level. For excited leptons, constraints are provided as functions of both the mass of the excited state and the compositeness scale Λ, with the strongest mass constraints arising in regions where the mass equals Λ. In such scenarios, lower mass limits are set at 3.0 TeV for excited electrons and muons, 2.5 TeV for excited taus, and 1.6 TeV for every excited-neutrino flavour. The ATLAS collaboration 44 IntroductionWith the delivery and exploitation of over 20 fb −1 of integrated luminosity at a centre-ofmass energy of 8 TeV in proton-proton collisions at the CERN Large Hadron Collider, many models of new physics now face significant constraints on their allowed parameter space. Final states including three or more charged, prompt, and isolated leptons have received significant attention, both in measurements of Standard Model (SM) diboson [1][2][3] and Higgs boson production [4,5], and in searches for new phenomena. Anomalous production of multi-lepton final states arises in many beyond the Standard Model (BSM) scenarios, including excited-lepton models [6,7], the Zee-Babu neutrino mass model [8][9][10], supersymmetry [11][12][13][14][15][16][17][18][19], models with pair production of vector-like quarks [20], and models with doubly charged Higgs bosons [21,22] including Higgs triplet models [23,24]. An absence of significant deviations from SM predictions in previous measurements and dedicated searches motivates an inclusive search strategy, sensitive to a variety of production modes and kinematic features.-1 - JHEP08(2015)138In this paper, the results of a search for the anomalous production of events with at least three charged leptons are presented. The dataset used was collected in 2012 by the ATLAS detector at the Large Hadron Collider, and corresponds to an integrated luminosity of 20.3 fb −1 of pp collisions at √ s = 8 TeV. Events with at least three leptons are categorized using their flavour content, and signal reg...

“…(2.1) are: Φ † Φ S, where Φ is the standard Higgs doublet and S is a singlet; Φ † τ a Φ T a , where T a is a scalar (real or complex) triplet [11,12]; Φ † τ a Φ c Ξ † t a X where Ξ is a zero hypercharge real triplet, X a Y = 1 complex triplet and Φ c is the charge conjugate of Φ, the so-called Georgi-Machacek model, see ref. [13]. For a classification of CP even scalars according to their properties JHEP05(2016)162 Figure 1.…”

Section: General Formalismmentioning

confidence: 99%

Low energy behaviour of standard model extensions

Boggia

Gómez-Ambrosio

Passarino

2016

The integration of heavy scalar fields is discussed in a class of BSM models, containing more that one representation for scalars and with mixing. The interplay between integrating out heavy scalars and the Standard Model decoupling limit is examined. In general, the latter cannot be obtained in terms of only one large scale and can only be achieved by imposing further assumptions on the couplings. Systematic low-energy expansions are derived in the more general, non-decoupling scenario, including mixed tree-loop and mixed heavy-light generated operators. The number of local operators is larger than the one usually reported in the literature.